A liquid crystal display (LCD) device essentially includes a plurality of data lines, a plurality of gate lines and a plurality of pixel units. Each pixel unit includes a first liquid-crystal capacitor, a second liquid-crystal capacitor, a first switch and a second switch. The first liquid-crystal capacitor of a pixel unit is charged via the first switch of the same pixel unit. The second liquid-crystal capacitor of a pixel unit is charged via the second switch of the same pixel unit and the first switch of a different pixel unit. The sub-pixel voltages corresponding to the first and second liquid-crystal capacitors of the same pixel unit have the same polarity. Furthermore, disclosed is a liquid-crystal display driving method for writing two data signals having same polarity respectively into the first and second liquid-crystal capacitors of a pixel unit via the same date line during two intervals partly overlapped.